1. Field of the Invention
The present invention relates to a work vehicle such as a tractor.
2. Description of the Related Art
[1] In a work vehicle, a setting screen selected by a setting information processing unit provided to an information displaying device thereof from among a plurality of set screens corresponding to a plurality of information items is displayed on a display, and the set information corresponding to the selected setting screen is changed.
For example, Japanese Laid-open Patent Publication 2009-143456 (JP 2009-143456 A) discloses a configuration comprising a display (a display unit in JP 2009-143456 A) for displaying various different information items of a vehicle body, a switch operational tool for switching the screen displayed on the display, and a setting operational tool for performing various different settings.
In JP 2009-143456 A, a plurality of basic screens can be switched by a switch operational tool and the display of the basic screen makes it possible to understand needed information from the screen. When, in a situation where a basic screen is being displayed, a setting button is operated, the selected screen corresponding to the basic screen is thereby displayed, and the display is made to display an operation guide for guiding the selection of a setting item being displayed on the selection screen. In a situation where both the selection screen and the operation guide are being displayed in this manner, it is possible to select a setting item and perform a setting by following the operation guide, and operating a change operational tool after such a setting makes it possible to complete the setting processing.
Japanese Laid-open Patent Publication 2010-013060 (JP 2010-013060 A) discloses a configuration (an information display system for a vehicle) in which a meter includes a display and with an operation input unit which can be operated by being pressed. In such a configuration, the display content is switched sequentially in a fixed sequence each time the operation input unit is pressed briefly (for example, for less than five seconds), and, when the operation input unit is pressed for a long time (for example, for at least five seconds), a sub-menu for selecting a desired change input screen from a plurality of change input screens is displayed. Within the sub-menu, when the operation input unit is pressed briefly, a cursor for indicating a change input menu is thereby sequentially moved, it being then possible to select a change input menu; when the operation input unit is pressed for a long time, an underlying sub-menu is thereby displayed and the setting content can be changed. The inputted content is confirmed and the sub-menu screen is restored when a operation-free state continues beyond an input confirmation interval (for example, for five seconds) after a change setting is inputted by the operation of the operation input unit in the change input screen.
In JP 2010-013060 A, when a single operation input unit constituted of the press-operated type is press-operated for only a short period of time, the display content of a display is thereby sequentially switched, and when the operation input unit is press-operated for a long period of time, the setting content is thereby changed.
As disclosed in JP 2009-143456 A and JP 2010-013060 A, the operation of switching the display content of the display by an operation performed by a worker makes it possible to understand the work situation from the display of the display, and to check a setting value, the operating situation of various machines, and the like.
The ability to change a setting by an operation involving a specific switch, as disclosed in JP 2009-143456 A, also sometimes leads to a false setting when the switch is operated mistakenly, for example, when the worker is unaware that the setting is being changed. In particular, setting the unit when fuel consumption is displayed, setting an operating mode when various machines are operated, clearing the value(s) of a trip meter, and other such operations are not very frequently performed, and setting by a service technician is preferred.
In view whereof, changing the mode of operation, as disclosed in JP 2010-013060 A, presumably renders it more difficult for a setting to be changed; however, as in JP 2010-013060 A, the screen is switched when the operation input unit is press-operated briefly, and a move is made to a screen making it possible to change a setting when the operation input unit is press-operated for a long time; even though the inputted content is confirmed by the elapsing of a period of time thereafter, it is impossible to avoid a false setting, and there remains room for improvement.
One object of the present invention is to provide a reasonable configuration for an information displaying device for suppressing the defect where set information corresponding to a setting screen displayed on a display is mistakenly changed while permitting an operation for switching to and displaying on a display a single one of a plurality of set screens.
[2] In a work vehicle, there is sometimes provided an authentication processing unit for allowing an engine to be started only when memory authentication information, which is pre-stored, and inputted authentication information, which is inputted, are identical to each other.
For example, in Japanese Laid-open Patent Publication 2008-162337 (JP 2008-162337 A), a configuration is such that a plurality of operation switches arranged on an operation panel can be used for password input switching; after an engine is started, when the plurality of operation switches is operated in a set sequence, the inputted sequence is understood to be a password, and continuous driving of the engine becomes possible when the password is identical to a previously set password.
In JP 2008-162337 A, the plurality of operation switches is to be used during work, and there is provided a controller (corresponding to an authentication processing unit) for acquiring information on the operation switches. A password (corresponding to authentication information) is set in a memory of the controller, and, when the inputted password (the sequence of operation of the plurality of operation switches) is identical to a previously set password, then, as described above, continuous driving of the engine is rendered possible, while when the passwords are not identical, then the controller performs a control for stopping the engine to prevent theft.
In Japanese Laid-open Patent Publication 2005-255134 (JP 2005-255134 A), the number of iterations where an engine key switch for starting an engine is operated to a start position is inputted as a cipher number, it being rendered possible to send power to a starter motor and start the engine only when the inputted cipher number is identical to a pre-set number of iterations.
JP 2005-255134 A discloses a configuration in which a signal system into which a signal from the engine key switch is inputted is provided to a theft prevention device (corresponding to the authentication processing unit) having a central processing unit (CPU), the cipher number (corresponding to the authentication information) being stored in an electrically erasable programmable read-only memory (EEPROM) of the theft prevention device. Thereby, it becomes possible to start the engine when the number of iterations where the engine key switch is operated to the start position is identical to the authentication number, and it becomes impossible to start the engine when the numbers are not identical, thus preventing theft.
Japanese Laid-open Patent Publication 2008-162337 (JP 2008-162337 A) discloses a configuration in which, when a pre-existing plurality of operation switches is operated, an authentication is thereby executed; when the number of operation switches used in the authentication is increased in order to enhance the precision of the authentication, more effort and time are needed, because the hands are moved more when the plurality of operation switches is operated. In contrast thereto, Japanese Laid-open Patent Publication 2005-255134 (JP 2005-255134 A) discloses a configuration in which the precision of the authentication is enhanced even while only a single engine key switch is to be used.
However, performing the authentication based on the number of iterations where a single switch is operated, as in the configuration of JP 2005-255134 A, also has limitations on enhancing the precision of the authentication, and there remains room for improvement.
One object of the present invention is to provide a reasonable configuration for a work vehicle for enhancing the precision of an authentication when an engine is to be started, while using a smaller number of switches.